Containers
Build, ship, and run anywhere
Docker solves the “it works on my machine” problem by packaging applications with all their dependencies into lightweight, portable units that run identically across development, testing, and production.
Why Learn Docker?
Containers buy four things: environment consistency (the same behavior on a laptop and in production), fast onboarding (a new contributor runs one docker run instead of spending days configuring tools), efficient resource use (higher density than virtual machines), and simple deployments (package once, deploy anywhere). They are the foundation of modern application delivery for developers and operations engineers alike.
Learning Path
Work through the guides in order, or jump to the one matching your task.
QUICK REFERENCE Docker Essentials is a side-by-side command cheat sheet, not a step in the sequential path above. Keep it open while you work through the guides.
Key Capabilities
Containers are lightweight (they share the host kernel), start in seconds rather than minutes, and run consistently anywhere. The contrast with virtual machines makes the trade-offs concrete:
| Capability | Containers | Virtual Machines |
|---|---|---|
| Startup time | Seconds | Minutes |
| Memory overhead | Minimal (shared kernel) | High (full OS per VM) |
| Disk usage | MBs | GBs |
| Isolation level | Process-level | Hardware-level |
| Best for | Microservices, CI/CD | Legacy apps, different OS |
See Also
- Docker Essentials - Quick command reference
- Container Runtimes - Runtimes beyond Docker
- Kubernetes - Container orchestration
- AWS ECS - Managed container service
- CI/CD - Continuous deployment